If the Brits go in, they should not leave until every ship in Argentina's navy is sunk, and Argentina's congressional building, presidential building, and military HQ are all smoking holes in the ground.
I don't think they have it in them to go that far, but that's what I think it will take to discourage Argentina from trying again in the near future.
It’s a question of both actually. Thirty years is a long time between wars and the UK’s military, especially The Royal Navy is not what it was thirty years ago, and even then due to Britain’s economic situation it was tough for them to pull it off. As it was they lost six ships and 200 men. And David Cameron is no Margret Thatcher. And you’re right, I just don’t think the Brits themselves have the will to do it.
Neither does the US have it in them to conduct such a pre-emptive strike on a country merely threatening with words or we would no longer have a North Korea, an Iran, a Venezuela, a Cuba etc, etc.